JP2001348569A - Phosphor for cathode ray tube and cathode ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the compactness of the fluorescent screen formed from a phosphor for cathode ray tubes whereby the performance of the cathode tube is increased and the image quality of the TV set using the same is heightened. SOLUTION: The particles of phosphor are coated on their surfaces with at least one selected from the group consisting of silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide and titanium oxide and carboxymethyl cellulose or propylene glycol alginate ester. The objective cathode ray tube is equipped with the fluorescent screen formed from such a phosphor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor used for a cathode ray tube of a color television, a computer display, and the like, and a cathode ray tube using such a phosphor.

[0002]

2. Description of the Related Art Generally, a fluorescent film of a cathode ray tube of a color television, a computer display or the like is formed as follows. A phosphor is prepared by dispersing a phosphor in an aqueous solution containing polyvinyl alcohol (PVA), ammonium bichromate (ADC) and a small amount of a surfactant, and the phosphor slurry is applied to the inner surface of a glass panel. To form a phosphor coating film. Next, the coating film is irradiated with ultraviolet rays through a shadow mask. At this time, since only the phosphor slurry present in the region irradiated with the ultraviolet rays is cured by the photochemical reaction, the phosphor slurry in the uncured portion is then rinsed with water to form a dot-shaped or stripe-shaped phosphor film. . This action is green,
The green, blue, and red phosphor films are formed by sequentially repeating the blue and red light-emitting phosphors.

When a phosphor film is formed by such a method, the properties required for each phosphor are as follows: (1) A dense dot-like or stripe-like phosphor film can be formed; (2) Dot- or stripe-shaped phosphor films have high quality, and (3) each phosphor does not mix with phosphors of other colors. That is, color mixing does not occur, (4) the adhesion to the inner surface of the glass panel is strong, (5) the yield of the phosphor film at the time of production is good, that is, for example, no phosphor residue remains on the side wall of the inner surface of the glass panel. That. In recent years, in particular, since high-performance, high-quality color televisions and the like have been demanded in the market, a high-quality phosphor that sufficiently satisfies the above requirements has been desired.

Conventionally, various developments and improvements have been made by performing surface treatments on the phosphors in order to satisfy the above-mentioned required characteristics of the phosphors.

For example, Japanese Patent Application Laid-Open No. 54-102299 discloses a treatment method in which a pigment-attached phosphor is brought into contact with a water-soluble organic compound solution to improve dispersibility.

Further, Japanese Patent Publication No. 60-21675 discloses zinc hydroxide (Zn (O)
H) The surface treatment of the phosphor by ₂ ) is disclosed in
No. 155983 discloses methods of surface-treating a phosphor with zinc oxide (ZnO) in order to improve adhesion and color mixing quality.

Further, Japanese Patent Publication No. 29403/1994 discloses an organic binder containing casein, in which inorganic compound particles such as silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) are adhered to the surface of a phosphor to mix colors. A technique for improving quality is disclosed.

[0008] Japanese Patent Application Laid-Open No. Hei 5-179235 discloses a technique in which a metal alginate is adhered via a water-soluble organic binder to prevent perforation of a fluorescent film and improve color mixing quality. .

[0009] However, none of the proposals is still sufficient in view of the recent high demand levels in the market. In particular, the red light-emitting phosphor, the red phosphor film, usually,
Since it is formed after the green fluorescent film and the blue fluorescent film, the green fluorescent film and the blue fluorescent film must be applied to the glass panel surface with large unevenness, so that a dense and high-quality fluorescent film is formed. It is necessary to further improve the dispersibility in the phosphor slurry, the fluidity of the phosphor slurry, and the like, but there has not yet been obtained one that sufficiently satisfies such requirements.

In recent years, the production index has been increased in order to improve the working efficiency in the production of a cathode ray tube. Therefore, there is a tendency that the drying temperature after the application of the phosphor slurry is increased to dry the phosphor. In some cases, membrane aggregation occurred during drying, resulting in large pores.

[0011]

As described above, various techniques have been proposed for improving the film quality of a phosphor film by treating the surface of the phosphor with an inorganic compound or an organic compound. It has not yet been provided with characteristics that can sufficiently meet high demand levels. Further, when the coating film of the phosphor slurry is dried at a high temperature, there is a possibility that the film is aggregated and large holes are formed. Against this background,
There is a strong demand for the development of a phosphor that can form a denser and higher-quality phosphor film, and that does not cause film agglomeration even when the phosphor slurry coating film is dried at high temperature and cause large pores. I have.

SUMMARY OF THE INVENTION The present invention has been made in order to address the above-mentioned problems, and it is an object of the present invention to provide a fluorescent material for a cathode ray tube capable of stably obtaining an extremely dense and high-quality fluorescent film, and to use such a fluorescent material. Accordingly, an object of the present invention is to provide a cathode ray tube capable of achieving higher performance and higher image quality.

[0013]

Means for Solving the Problems To solve the above problems, a phosphor for a cathode ray tube according to the first aspect of the present invention is
The surface of the phosphor particles is coated with at least one selected from the group consisting of silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide and titanium oxide, and carboxymethyl cellulose. It is characterized by having.

In the phosphor for a cathode ray tube according to the present invention, the coating amount of carboxymethyl cellulose is preferably 0.005 to 0.3% by weight based on the phosphor particles.

The carboxymethyl cellulose preferably has a degree of etherification of 0.8 to 1.0.

[0016] In order to solve the above-mentioned problems, the present invention is directed to claim 4 of the present application.
The phosphor for a cathode ray tube according to the invention described above, on the surface of the phosphor particles, at least selected from the group consisting of silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide and titanium oxide.
One type and a propylene glycol alginate are coated.

In the phosphor for a cathode ray tube of the present invention, the coating amount of propylene glycol alginate is 0.005 to 0.3 with respect to the phosphor particles.
% By weight.

In the above-described phosphor for a cathode ray tube according to the present invention, the surface of the phosphor particles is further coated with at least one selected from the group consisting of sulfate and nitrate. Preferably, at least one selected from the group consisting of such sulfates and nitrates is zinc sulfate, as described in claim 7,
More preferably, it is at least one selected from the group consisting of aluminum sulfate, potassium sulfate, lithium sulfate, sodium sulfate, aluminum nitrate, barium nitrate, calcium nitrate, sodium nitrate and strontium nitrate.

The coating amount of at least one selected from the group consisting of sulfate and nitrate may be in the range of ²⁰ to 300 μS / cm ^{2 in} electrical conductivity. preferable. Here, the electric conductivity is 10
g was dispersed in 100 ml of pure water, stirred for 1 hour, and allowed to stand for 3 hours, and the electric conductivity of the supernatant was measured using an electric conductivity meter.

[0020] In order to solve the above-mentioned problem, a ninth aspect of the present invention will be described.
A cathode ray tube according to the invention described above is characterized by comprising a phosphor film containing the phosphor for a cathode ray tube according to the invention described above.

As a specific configuration of the cathode ray tube according to the present invention, as described in claim 10, a panel constituting an envelope, a fluorescent film formed on the inner surface of the panel, and an electron A cathode ray tube including an electron gun for irradiating a ray, wherein the fluorescent film includes the above-described phosphor for a cathode ray tube of the present invention.

In the phosphor for a cathode ray tube of the present invention, the surface of the phosphor particles is selected from the group consisting of silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide and titanium oxide. Carboxymethylcellulose or propylene glycol alginate. By performing such a coating treatment, the dispersibility of the phosphor in the phosphor slurry is improved, and the fluidity of the phosphor slurry is enhanced. Also,
Film aggregation when drying the phosphor slurry coating film is suppressed. Therefore, it is possible to stably form a fluorescent film having significantly improved denseness and uniformity.

The cathode ray tube of the present invention having the phosphor film containing such a phosphor for a cathode ray tube can achieve high performance and high image quality by improving the film quality of the phosphor film.

[0024]

Embodiments of the present invention will be described below.

The phosphor for a cathode ray tube according to the present invention comprises: (a) silicon dioxide, zinc silicate, zinc hydroxide,
At least one selected from the group consisting of zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide and titanium oxide, and (b) carboxymethylcellulose or (c) propylene glycol alginate is coated. .

As the phosphor material in the phosphor for a cathode ray tube of the present invention, there is usually used a cathode ray tube, including a pigment-coated phosphor used in a high-contrast color television cathode-ray tube in which the surface of the phosphor particles is coated with pigment particles. A variety of available blue, green and red emitting phosphors can be used. Specifically, silver activated zinc sulfide phosphor, silver and aluminum activated zinc sulfide phosphor, cobalt blue pigment coated silver activated zinc sulfide phosphor, cobalt blue pigment coated silver and aluminum activated zinc sulfide phosphor, etc. Blue light-emitting phosphor, copper and aluminum activated zinc sulfide phosphor,
Examples include green light-emitting phosphors such as copper, gold, and aluminum-activated zinc sulfide phosphors, red light-emitting phosphors such as europium-activated yttrium oxysulfide phosphors, and europium-activated europium-activated yttrium oxysulfide phosphors coated with red iron oxide. In addition,
In the pigment-coated phosphor, a binder such as gelatin, gum arabic, or an acrylic resin is used in order to attach the pigment to the surface of the phosphor particles, but the pigment-coated phosphor using any binder is used. Can also be used for the phosphor for a cathode ray tube of the present invention.

A group consisting of silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide and titanium oxide of the above-mentioned component (a) to be coated on the particle surface of such a phosphor. At least one selected from 0.001 to 0.
The coating is preferably performed in the range of 8% by weight, more preferably in the range of 0.01 to 0.5% by weight based on the phosphor particles.

When the coating amount of the component (a) is less than 0.001% by weight based on the phosphor particles, the effect of improving the denseness of the phosphor film cannot be sufficiently obtained. In this case, the dispersibility of the phosphor may be reduced, and defects such as color mixing may occur.

The carboxymethyl cellulose of the component (b) is obtained by substituting the hydroxyl group of cellulose with a sodium carboxymethyl group. In the present invention, the degree of substitution with the sodium carboxymethyl group, that is, the degree of etherification is 0.8 to 1.0. It is preferable to use those in the range of The carboxymethyl cellulose of the component (b) is preferably coated in the range of 0.005 to 0.3% by weight based on the phosphor particles, and more preferably in the range of 0.01 to 0.2% by weight based on the phosphor particles. When the coating amount of the carboxymethyl cellulose of the component (b) is less than 0.005% by weight with respect to the phosphor particles, the fluidity of the phosphor slurry does not increase, and the quality of the phosphor film may not be sufficiently improved. On the other hand, if the content exceeds 0.3% by weight, the phosphor becomes a hard block in the drying step after coating, the mesh passing during the sieving process is deteriorated, and the workability becomes poor. Further, the fluorescent substance is easily aggregated, and the denseness of the fluorescent film is reduced.

The propylene glycol alginate component (c) is obtained by introducing a propylene glycol group into a carboxyl group of alginic acid and esterifying the same. Therefore, unlike alginate, it depends on the type of cation paired with the carboxyl group. It has the characteristic that the physical properties do not change and it is stable to acids and alkalis. The propylene glycol alginate of the component (c) is preferably coated in the range of 0.005 to 0.3% by weight to the phosphor particles, and more preferably in the range of 0.01 to 0.2% by weight to the phosphor particles. When the coating amount of the propylene glycol alginate of the component (c) is less than 0.005% by weight based on the phosphor particles, the fluidity of the phosphor slurry does not increase, and the quality of the phosphor film may not be sufficiently improved. . On the other hand, if the content exceeds 0.3% by weight, the phosphor becomes a hard block in the drying step after coating, the mesh passing during the sieving process is deteriorated, and the workability becomes poor. Further, the fluorescent substance is easily aggregated, and the denseness of the fluorescent film is reduced.

In the phosphor for a cathode ray tube of the present invention, the above-mentioned component (a) of silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide, At least one selected from the group consisting of aluminum and titanium oxide,
(B) carboxymethyl cellulose of the component, or
By coating the propylene glycol alginate component (c), the dispersibility of the phosphor in the phosphor slurry and the fluidity of the phosphor slurry can be increased. Film aggregation can be suppressed. Thereby, the denseness and uniformity of the fluorescent film can be significantly improved. Also,
By improving the denseness of the phosphor film, the quality of the phosphor film can be improved, and a phosphor film having less meandering stripes and dot edges can be formed.

In the phosphor for a cathode ray tube of the present invention, the surface of the phosphor particles may be further coated with at least one selected from the group consisting of (d) sulfate and nitrate. In particular, when coating (b) carboxymethylcellulose, it is preferable to coat together with such a component (d).

That is, together with at least one selected from the group consisting of sulfates and nitrates of the component (d),
The phosphor coated with carboxymethylcellulose as the component (b) is less likely to undergo film aggregation when the phosphor slurry coating film is dried than the phosphor not coated with the component (d). It is even better than when such a sulfate or nitrate is added during slurry preparation. It is considered that this is because carboxymethyl cellulose and a part of ions of sulfate or nitrate are combined in the drying step after coating with carboxymethyl cellulose or the like.

Examples of the sulfate and nitrate of the component (c) include zinc sulfate, aluminum sulfate, potassium sulfate, lithium sulfate, sodium sulfate, aluminum nitrate, barium nitrate, calcium nitrate, sodium nitrate and strontium nitrate. It is preferable to use at least one selected from these.

At least one selected from the group consisting of the sulfates and nitrates of the component (c) has an electric conductivity of at least 20%.
It is preferable to coat within a range of ~ 300 μS / cm ² ,
It is more preferable that the coating be performed in a range of 30 to 150 μS / cm ² in electric conductivity. If the coating amount has an electric conductivity of less than 20 μS / cm ² , the effect of the coating is small, and if the electric conductivity exceeds 300 μS / cm ² , defects such as color mixing tend to occur.

In preparing the phosphor for a cathode ray tube of the present invention, first, silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, zinc silicate Aluminum, aluminum hydroxide, at least one selected from the group consisting of aluminum oxide and titanium oxide coating treatment, then carboxymethyl cellulose or propylene glycol alginate, or carboxymethyl cellulose or propylene glycol alginate,
At least one selected from the group consisting of sulfates and nitrates
It is preferable to perform the coating treatment together with one kind.

The temperature for drying after coating the surface of the phosphor particles with carboxymethyl cellulose or the like is preferably in the range of 100 to 180 ° C. Drying temperature is 18
If the temperature is higher than 0 ° C, carboxymethylcellulose or propylene glycol alginate will be deteriorated. Conversely, if the drying temperature is lower than 100 ° C, drying takes a long time and the workability is reduced. A more preferable range of the drying temperature is 110 to 150 ° C.

The cathode ray tube of the present invention is provided with a phosphor film using the phosphor for a cathode ray tube of the present invention as described above. FIG. 1 shows a color cathode ray tube, which is one embodiment of the present invention.

This color cathode ray tube comprises a panel 1 and a funnel 2 constituting an envelope, a fluorescent film 3 formed on the inner surface of the panel 1, and an electron gun 5 for irradiating the fluorescent film 3 with an electron beam 4. Have. The blue, green and red light emitting phosphors for the cathode ray tube of the present invention are used as the blue, green and red light emitting phosphors forming the fluorescent film 3. In FIG. 1, reference numeral 6 denotes a shadow mask;
Is an inner shield, and 8 is a polarizing device.

In such a color CRT,
It is possible to obtain the fluorescent film 3 which is dense and has good cutting quality, and high performance and high image quality can be achieved.

[0041]

Next, specific examples of the present invention and evaluation results thereof will be described. The carboxymethyl cellulose used in the following examples is sodium carboxymethyl cellulose having a degree of etherification of 0.93.

Example 1 First, a copper / aluminum activated zinc sulfide phosphor (ZnS:
1 kg of Cu, Al phosphor particles were suspended in 6 L (liter) of pure water. 5 ml of water glass (containing 25% of Si) is added to this suspension, and then 10 ml of a 10% colloidal silica solution
, And stirred for 20 minutes.
0 ml was added and the mixture was stirred for 30 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, the phosphor particles were washed three times with 8 L of pure water, and then 300 ml of a 1% carboxymethylcellulose aqueous solution was added.
And then 30 ml of an 8% aqueous zinc nitrate solution.
Pure water was added until the total volume became 1 L, followed by stirring for 60 minutes.

Thereafter, this was directly filtered and dried at 120 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

As a result of analyzing the phosphor thus obtained, the surface of the ZnS: Cu, Al phosphor particles was 0.1% by weight of silica, 0.022% by weight of zinc silicate, 0.1% by weight with respect to the phosphor particles. Of carboxymethylcellulose and zinc nitrate in an amount to give an electric conductivity of 40 μS / cm ² .

Using the obtained phosphor, a phosphor slurry was prepared by an ordinary method, and the phosphor slurry was uniformly applied to the inner surface of a glass panel for a color cathode-ray tube by an ordinary method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. By the way, the perforated quality of the phosphor film was evaluated by the 10-point method with five usable levels (the higher the score, the higher the film quality). The score was 5 points, whereas the score of the fluorescent film using the phosphor of this example was 7 points.

Example 2 1 kg of silver / chlorine activated zinc sulfide phosphor (ZnS: Ag, Cl phosphor) particles were suspended in 6 L of pure water. 5 ml of a 10% alumina solution was added to this suspension, followed by 50 ml of an 8% zinc sulfate solution, and the pH was adjusted with dilute aqueous ammonia with stirring.
Adjusted to 8.5 and stirred for 60 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, the above phosphor particles were washed three times with 8 L of pure water, and then 800 ml of a 1% aqueous solution of carboxymethyl cellulose.
Was added, and 20 ml of an aqueous 8% aluminum nitrate solution was further added. Then, pure water was added until the total volume became 1 L, followed by stirring for 60 minutes.

Thereafter, this was directly filtered and dried at 150 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

Analysis of the phosphor thus obtained revealed that the surface of the ZnS: Ag, Cl phosphor particles was 0.05% by weight of alumina, 0.12% by weight of zinc oxide, 0.25% by weight with respect to the phosphor particles. Of carboxymethylcellulose, and an amount of aluminum nitrate having an electric conductivity of 30 μS / cm ² .

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied to the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. By the way, the result of evaluating the perforated quality of the fluorescent film by the same 10-point method as in Example 1 was that the fluorescent film using the phosphor without surface treatment was 6 points, The number of the phosphor films using the phosphor was eight.

Example 3 A silver / chlorine-activated zinc sulfide phosphor (ZnS: Ag, C) coated with a cobalt blue pigment using an acrylic resin as a binder
1 phosphor) 1 kg of particles were suspended in 6 L of pure water. To this suspension was added 30 ml of a 10% colloidal silica solution, then 25 ml of a 10% aluminum nitrate solution, the pH was adjusted to 9 with dilute aqueous ammonia with stirring, and the mixture was stirred for 60 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, the above phosphor particles were washed three times with 8 L of pure water, and then 100 ml of a 1% carboxymethylcellulose aqueous solution was added.
Was added, and 150 ml of an 8% aqueous sodium sulfate solution was further added. Then, pure water was added until the total amount became 1 L, followed by stirring for 60 minutes.

Thereafter, this was directly filtered and dried at 100 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

As a result of analyzing the phosphor thus obtained, the surface of the ZnS: Ag, Cl phosphor particles coated with the cobalt blue pigment showed 0.05% by weight of silica and 0.05% by weight of Aluminum, 0.03% by weight carboxymethylcellulose, and electric conductivity 170μ
It was found that it was coated with aluminum nitrate in an amount of S / cm ² .

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied to the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. By the way, the result of evaluating the perforated quality of the fluorescent film by the same 10-point method as in Example 1 was 6.5 points for the fluorescent film using the phosphor without surface treatment, whereas the result of this example was The number of the phosphor films using the phosphor was eight.

Example 4 Europium-activated yttrium oxysulfide phosphor (Y ₂ O
₂ S: Eu phosphor) particles 1kg was suspended in pure water 6 L. 5 ml of 10% titanium oxide solution and 10% in this suspension
5 ml of colloidal silica solution was added and stirred for 20 minutes. Next, 30 ml of an 8% zinc sulfate solution was added, the pH was adjusted to 9 with dilute aqueous ammonia with stirring, and the mixture was stirred for 60 minutes. After stirring,
The phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, the above phosphor particles were washed three times with 8 L of pure water, and then 100 ml of a 1% aqueous solution of carboxymethyl cellulose.
Was added, and 80 ml of an 8% lithium nitrate aqueous solution was further added. Then, pure water was added until the total amount became 1 L, followed by stirring for 60 minutes.

Thereafter, this was directly filtered and dried at 100 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

As a result of analyzing the phosphor thus obtained, the surface of the Y ₂ O ₂ S: Eu phosphor particles was 0.05% by weight of silica, 0.05% by weight of titanium oxide,
It was found to be coated with 0.065% by weight of zinc hydroxide, 0.07% by weight of carboxymethylcellulose and an amount of lithium nitrate having an electric conductivity of 80 μS / cm ² .

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied to the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. By the way, the result of evaluating the perforated quality of the fluorescent film by the same 10-point method as in Example 1 was 6.5 points for the fluorescent film using the phosphor without surface treatment, whereas the result of this example was 8.5 fluorescent film using phosphor
Was a point.

Example 5 Europium-activated yttrium oxysulfide phosphor coated with red iron oxide using an acrylic resin as a binder (Y ₂ O
₂ S: Eu phosphor) particles 1kg was suspended in pure water 6 L. To this suspension was added 30 ml of a 10% colloidal silica solution, followed by 5 ml of water glass (containing 25% Si) to add 1 ml.
After stirring for 0 hour, 2 ml of 50% aluminum sulfate solution
And adjust the pH with a 10% aqueous potassium hydroxide solution while stirring.
Adjusted to 5.8 and stirred for 60 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, the above-mentioned phosphor particles were washed three times with 8 L of pure water, and then 30 ml of a 1% aqueous solution of carboxymethyl cellulose.
After adding 70 ml of an 8% aqueous zinc sulfate solution,
Pure water was added until the total volume became 1 L, followed by stirring for 60 minutes.

Thereafter, this was directly filtered and dried at 120 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

[0065] Analysis of the thus-obtained phosphor, red iron oxide pigment coated Y ₂ O ₂ S: surface of the Eu phosphor particles, 0.1 wt% of silica with respect to the phosphor particles, 0.035 wt% silicate It was found to be coated with aluminum, 0.01% by weight carboxymethylcellulose, and zinc sulfate in an amount to provide an electrical conductivity of 70 μS / cm ² .

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied to the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. By the way, the result of evaluating the perforated quality of the fluorescent film by the same 10-point method as in Example 1 was 5 points for the fluorescent film using the phosphor without surface treatment, whereas the result of this example was 5 points. The number of the phosphor films using the phosphor was eight.

FIGS. 2 and 3 are micrographs (magnification: 35 times) of the fluorescent film taken before the development after the phosphor slurry was applied to the inner surface of the glass panel and dried, and FIG. FIG. 3 shows a phosphor film using a phosphor, and FIG. 3 shows a phosphor film using a phosphor without surface treatment. As is clear from these photographs, the phosphor film using the phosphor of this example is
Compared with a phosphor film using a phosphor without surface treatment, it has less holes and is dense.

Example 6 A copper / aluminum activated zinc sulfide phosphor (ZnS: Cu,
1 kg of Al phosphor particles were suspended in 6 L of pure water. 5 ml of water glass (containing 25% of Si) is added to this suspension,
Next, 10 cc of a 10% colloidal silica solution was added and stirred for 20 minutes, and then 50 ml of an 8% zinc sulfate solution was added and stirred for 30 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, after washing the phosphor particles three times with 8 L of pure water, 300 ml of a 1% aqueous solution of propylene glycol alginate was added, and pure water was added until the total volume became 1 L, followed by stirring for 60 minutes. did.

Thereafter, this was directly filtered and dried at 120 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

As a result of analyzing the phosphor thus obtained, it was found that the surface of the ZnS: Cu, Al phosphor particles was 0.1% by weight of silica, 0.022% by weight of zinc silicate, 0.1% by weight based on the phosphor particles. Was found to be coated with propylene glycol alginate.

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied on the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. The cut quality was also good. By the way, the result of evaluating the perforated quality of the fluorescent film by the same 10-point method as in Example 1 was 5 points for the fluorescent film using the phosphor without surface treatment, whereas the result of this example was 5 points. The number of the phosphor films using the phosphor was eight. In addition, as in the case of the perforated quality, the quality of the phosphor film was evaluated by the 10-point method with the usable level being 5 points. On the other hand, the number of the phosphor films using the phosphor of this example was eight. The cut quality is evaluated based on the difference between the maximum width and the minimum width of the stripe of the fluorescent film formed in a stripe shape. The smaller the difference, the better the cut quality.

Example 7 1 kg of silver / chlorine activated zinc sulfide phosphor (ZnS: Ag, Cl phosphor) particles were suspended in 6 L of pure water. 5 ml of a 10% alumina solution was added to this suspension, followed by 50 ml of an 8% zinc sulfate solution, and the pH was adjusted with dilute aqueous ammonia with stirring.
Adjusted to 8.5 and stirred for 60 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, after washing the phosphor particles three times with 8 L of pure water, 800 ml of a 1% aqueous solution of propylene glycol alginate was added, and pure water was added until the total volume became 1 L, followed by stirring for 60 minutes. did.

Thereafter, this was directly filtered and dried at 150 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

Analysis of the phosphor thus obtained showed that the surface of the ZnS: Ag, Cl phosphor particles was 0.05% by weight of alumina, 0.12% by weight of zinc oxide, 0.25% by weight with respect to the phosphor particles. Was found to be coated with propylene glycol alginate.

Using the obtained phosphor, a phosphor slurry is prepared by a conventional method, and the phosphor slurry is uniformly applied on the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. did. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. The cut quality was also good. By the way, the perforated quality of the fluorescent film was measured in Example 1.
As a result of evaluation by the same 10-point method as in the case of the above, 6 points were obtained for the phosphor film using the phosphor without surface treatment, whereas 8 points were obtained for the phosphor film using the phosphor of this example. Was. In addition, the result of the evaluation of the cutting quality of the phosphor film by the same 10-point method as in the case of Example 6 shows that the phosphor film using the phosphor without surface treatment was 6 points.
On the other hand, the number of the fluorescent films using the phosphor of the present example was 7 in comparison with the number of points.

Example 8 A silver / chlorine activated zinc sulfide phosphor (ZnS: Ag, C) coated with a cobalt blue pigment using an acrylic resin as a binder
1 phosphor) 1 kg of particles were suspended in 6 L of pure water. To this suspension was added 30 ml of a 10% colloidal silica solution, then 25 ml of a 10% aluminum nitrate solution, the pH was adjusted to 9 with dilute aqueous ammonia with stirring, and the mixture was stirred for 60 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, after washing the phosphor particles three times with 8 L of pure water, 100 ml of a 1% aqueous solution of propylene glycol alginate was added, and pure water was added until the total volume became 1 L, followed by stirring for 60 minutes. did.

Thereafter, this was directly filtered and dried at 100 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

As a result of analyzing the phosphor thus obtained, the surface of the cobalt blue pigment-coated ZnS: Ag, Cl phosphor particles was 0.3% by weight of silica and 0.05% by weight of hydroxide based on the phosphor particles. Aluminum was found to be coated with 0.03% by weight propylene glycol alginate.

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied to the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. The cut quality was also good. By the way, the result of evaluating the perforated quality of the fluorescent film by the same 10-point method as in Example 1 was 6.5 points for the fluorescent film using the phosphor without surface treatment, whereas the result of this example was The number of the phosphor films using the phosphor was 9 points. In addition, the result of evaluating the quality of the fluorescent film by the same 10-point method as in Example 6 was that the fluorescent film using the phosphor without surface treatment had 6 points, whereas the fluorescent film of the present example had 6 points. 8 fluorescent screens
Was a point.

Example 9 Europium-activated yttrium oxysulfide phosphor (Y ₂ O
₂ S: Eu phosphor) particles 1kg was suspended in pure water 6 L. 5 ml of 10% titanium oxide solution and 10% in this suspension
5 ml of colloidal silica solution was added and stirred for 20 minutes. Next, 30 ml of an 8% zinc sulfate solution was added, the pH was adjusted to 9 with dilute aqueous ammonia with stirring, and the mixture was stirred for 60 minutes. After stirring,
The phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, after washing the above phosphor particles three times with 8 L of pure water, 200 ml of a 1% aqueous solution of propylene glycol alginate was added, and pure water was added until the total volume became 1 L, followed by stirring for 60 minutes. did.

Thereafter, this was directly filtered and dried at 100 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

As a result of analyzing the phosphor thus obtained, the surface of the Y ₂ O ₂ S: Eu phosphor particles was 0.05% by weight silica, 0.05% by weight titanium oxide,
It was found to be coated with 0.065% by weight zinc hydroxide and 0.07% by weight propylene glycol alginate.

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied to the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. The cut quality was also good. By the way, the result of evaluating the perforated quality of the fluorescent film by the same 10-point method as in Example 1 was 5 points for the fluorescent film using the phosphor without surface treatment, whereas the result of this example was 5 points. The number of phosphor films using the phosphor was 8.5. In addition, the result of evaluating the quality of the fluorescent film by the same 10-point method as in Example 6 was that the fluorescent film using the phosphor without surface treatment had 6 points, whereas the fluorescent film of the present example had 6 points. 8 fluorescent screens
Was a point.

Example 10 Europium-activated yttrium oxysulfide phosphor coated with red iron oxide using an acrylic resin as a binder (Y ₂ O
₂ S: Eu phosphor) particles 1kg was suspended in pure water 6 L. To this suspension was added 30 ml of a 10% colloidal silica solution, and then 1 ml of water glass (containing 25% of Si).
After stirring for 0 hour, 2 ml of 50% aluminum sulfate solution
And adjust the pH with a 10% aqueous potassium hydroxide solution while stirring.
Adjusted to 5.8 and stirred for 60 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, after washing the phosphor particles three times with 8 L of pure water, 30 ml of a 1% aqueous solution of propylene glycol alginate was added, and pure water was added until the total volume became 1 L, followed by stirring for 60 minutes. did.

Thereafter, this was directly filtered and dried at 120 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

As a result of analyzing the phosphor thus obtained, it was found that the surface of the Vengara pigment-coated Y ₂ O ₂ S: Eu phosphor particles showed 0.1% by weight of silica and 0.035% by weight of silica It was found to be coated with aluminum and 0.01% by weight of propylene glycol alginate.

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied to the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. The cut quality was also good. By the way, the result of evaluating the perforated quality of the fluorescent film by the same 10-point method as in Example 1 was 6 points for the fluorescent film using the phosphor without surface treatment, whereas The number of the phosphor films using the phosphor was eight. In addition, the evaluation of the quality of the fluorescent film by the same 10-point method as in Example 6 showed that the fluorescent film using the phosphor without surface treatment had 5 points, whereas the fluorescent film of this example had 5 points. The number of phosphor films using the body was 7 points.

FIG. 4 is a photomicrograph (magnification: 35 ×) of the phosphor film taken before the development after the phosphor slurry was applied to the inner surface of the glass panel and dried, and the phosphor without surface treatment shown in FIG. 3 was used. Compared to a fluorescent film using, a hole is clearly less and dense.

Example 11 Europium-activated yttrium oxysulfide phosphor coated with red iron oxide using an acrylic resin as a binder (Y ₂ O
₂ S: Eu phosphor) particles 1kg was suspended in pure water 6 L. To this suspension was added 10 ml of a 10% colloidal silica solution, and then 2 ml of water glass (containing 25% Si) to add 1 ml.
After stirring for 0 hours, 20 ml of an 8% zinc sulfate solution was added,
Stir for 30 minutes. After stirring, the phosphor particles were allowed to settle, and the supernatant was removed by decantation.

Next, after washing the above phosphor particles three times with 8 L of pure water, 60 ml of a 1% aqueous solution of propylene glycol alginate was added, and 50 ml of an 8% aqueous solution of zinc sulfate were further added.
, Pure water was added until the total volume became 1 L, and the mixture was stirred for 60 minutes.

Thereafter, this was directly filtered and dried at 120 ° C. for 10 hours. After drying, a sieving process was performed using a 400-mesh sieve to obtain a phosphor of the present invention.

[0097] Analysis of the thus-obtained phosphor, red iron oxide pigment coated Y ₂ O ₂ S: surface of the Eu phosphor particles, 0.1 wt% of silica with respect to the phosphor particles, 0.01 wt% silicate It was found to be coated with zinc, 0.015% by weight propylene glycol alginate, and zinc sulfate in an amount to provide an electrical conductivity of 50 μS / cm ² .

Using the obtained phosphor, a phosphor slurry was prepared by a conventional method, and the phosphor slurry was uniformly applied on the inner surface of a glass panel for a color cathode-ray tube by a conventional method to form a phosphor film. Observation of the state of the phosphor film thus formed by an optical microscope revealed that the phosphor film had less holes and was more dense than a phosphor film formed using a phosphor without surface treatment. The cut quality was also good. By the way, the result of evaluating the perforated quality of the phosphor film by the same 10-point method as in Example 1 was 5.5 points for the phosphor film using the phosphor without surface treatment, whereas the result of this example was 5.5 points. The number of the phosphor films using the phosphor was eight. In addition, the evaluation of the quality of the fluorescent film by the same 10-point method as in Example 6 showed that the fluorescent film using the phosphor without surface treatment had 5 points, whereas the fluorescent film of this example had 5 points. The fluorescent film using the body is 7
Was a point.

[0099]

As described above, according to the present invention,
Since the surface treatment is performed on the phosphor with a specific inorganic compound and a specific organic compound such as carboxymethylcellulose or propylene glycol alginate, an extremely dense and high-quality fluorescent film can be stably formed. A phosphor for a cathode ray tube can be obtained.

Further, according to the cathode ray tube of the present invention using such a phosphor for a cathode ray tube, high performance and high image quality can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing a configuration of a main part of an embodiment of a cathode ray tube of the present invention.

FIG. 2 is a micrograph of a phosphor film (before development) formed using a phosphor for a cathode ray tube according to one embodiment of the present invention.

FIG. 3 is a micrograph of a phosphor film (before development) formed using a phosphor for a cathode ray tube without surface treatment.

FIG. 4 is a micrograph of a phosphor film (before development) formed using a phosphor for a cathode ray tube according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Panel 3 ... Fluorescent film 4 ... Electron beam 5 ... Electron gun

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4H001 CA01 CA06 CC03 CC05 CC09 CC10 CC11 CC13 XA08 XA16 XA30 XA39 YA13 YA17 YA29 YA47 YA63

Claims (10)

[Claims] 1. A phosphor particle comprising at least one selected from the group consisting of silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide and titanium oxide, on a surface of a phosphor particle. A phosphor for a cathode ray tube, which is coated with methylcellulose. 2. The phosphor for a cathode ray tube according to claim 1, wherein the coating amount of carboxymethyl cellulose is 0.005 to 0.3% by weight based on the phosphor particles. 3. The phosphor for a cathode ray tube according to claim 1, wherein the carboxymethylcellulose has a degree of etherification of 0.8 to 0.8.
A phosphor for a cathode ray tube, which is 1.0. 4. At least one member selected from the group consisting of silicon dioxide, zinc silicate, zinc hydroxide, zinc oxide, aluminum silicate, aluminum hydroxide, aluminum oxide and titanium oxide is formed on the surface of the phosphor particles, and alginic acid A phosphor for a cathode ray tube, which is coated with propylene glycol ester. 5. The phosphor for a cathode ray tube according to claim 4, wherein the coating amount of propylene glycol alginate is:
A phosphor for a cathode ray tube, which is 0.005 to 0.3% by weight based on the phosphor particles. 6. The phosphor for a cathode ray tube according to claim 1, wherein the surface of the phosphor particles is further coated with at least one selected from the group consisting of sulfate and nitrate. A phosphor for a cathode ray tube, characterized in that: 7. The phosphor for a cathode ray tube according to claim 6, wherein at least one selected from the group consisting of sulfate and nitrate.
One type is zinc sulfate, aluminum sulfate, potassium sulfate,
At least one selected from the group consisting of lithium sulfate, sodium sulfate, aluminum nitrate, barium nitrate, calcium nitrate, sodium nitrate and strontium nitrate
A phosphor for a cathode ray tube, which is a seed. 8. The phosphor for a cathode ray tube according to claim 6, wherein at least one selected from the group consisting of sulfate and nitrate.
A phosphor for a cathode ray tube, wherein one kind of coating amount is in a range of ²⁰ to 300 μS / cm ^{2 in} electric conductivity. 9. A cathode ray tube comprising a phosphor film containing the phosphor for a cathode ray tube according to claim 1. Description: 10. A cathode ray tube comprising: a panel constituting an envelope; a fluorescent film formed on an inner surface of the panel; and an electron gun for irradiating the fluorescent film with an electron beam. Item 9. A cathode ray tube comprising the phosphor for a cathode ray tube according to any one of Items 1 to 8.